The cardiovascular system. We’ve all got one. We all know circulation of blood is fundamental to our survival. But what is the primary purpose of the cardiovascular system? And why is it so important? Together with the respiratory system, the cardiovascular (CV) system it is responsible for delivering oxygen and nutrients to the body’s tissues, while at the same time removing waste such as carbon dioxide and other metabolic waste products. As fitness professionals, a significant portion of our focus is on increasing CV capacity, CV fitness, and CV health.

We can consider the CV system a closed – circuit system comprised of the heart, blood vessels and blood. As you are studying for your certification exam, you might be asked ‘can you follow a drop of blood through the circulatory system?’

When you are asked to trace the route of blood, the first question is, where are you starting? Let’s follow a freshly oxygenated drop of blood as it leaves the lungs…

Blood leaves the lungs and enters the left side of the heart through the pulmonary veins

Blood enters the left atrium, travels through the mitral valve, into the left ventricle

Blood leaves the left ventricle, travels through the aortic valve, and up into the aorta

Blood enters the aorta and is distributed throughout the body (but not to the lungs!)

Blood travels through progressively smaller paths – from arteries, to arterioles, to capillaries (this is often where a lot of the oxygen is transferred to working muscles etc), to venules (little veins), to veins, and back to the heart

Blood (now de-oxygenated) returns to the heart via the superior and inferior vena cava (one from the top your body, one from the bottom of your body)

Blood enters the right atrium from the superior/inferior vena cava, then travels through the tricuspid valve to the right ventricle

Finally, blood leaves the right ventricle and travels into the right and left pulmonary arteries, which take it back to the lungs to pick up some more oxygen

Improving a client’s CV function is a fundamental task for fitness professionals. If you have a client performing aerobic exercise, the greater their ability to get oxygen to the working muscles (through the CV system to the capillaries where it can be utilized) the longer the client can maintain the ‘aerobic’ part of their exercise (otherwise known as the greater their Max Vo2 is)

Questions? Contact an Education Consultant at 1-888-825-3636 x782

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